A light emitting diode (LED) is a semiconductor device that generates light using a light emitting phenomenon by combination of electrons and holes. As a material of an LED chip, a compound semiconductor, such as GaN, GaAs, GaP, GaAsP, GaAlAs, SiC, InP, InGaP or the like, is used. An LED has advantages of high energy efficiency, low operating voltage, small size, and long lifespan.
Related art is disclosed in Korean Patent No. 0915118 (Title: Module Type LED Display Block, Registration Date: Aug. 26, 2009).